


Monster Heart.

by My_Love_Letter



Category: Undertale (Video Game)
Genre: F/F, F/M, M/M, i might but idk yet., not really sure if I want to indulge in more reader ships
Language: English
Status: Completed
Published: 2018-10-13
Updated: 2018-10-13
Packaged: 2019-08-01 16:22:49
Rating: General Audiences
Warnings: Major Character Death
Chapters: 1
Words: 2,210
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16287887
Author URL: https://archiveofourown.org/users/My_Love_Letter/pseuds/My_Love_Letter
Summary: The reader is a cousin to Frisk who is trying to become their legal guardian. After a camping trip gone wrong, they have to survive the underground with their younger companion.It's kill or be killed.





	Monster Heart.

You had a small weekend away from work and school and had made an earlier promise to Frisk if they kept their grades up that you’d take them camping. With good timing, you managed to snag 3 days to go camping at the base of Mount Ebott. The time you spent together was fun and memorable, but it was time to leave and Frisk was having none of that. “C’mon, Frisk. Let’s go home,” you signed. The little 6 year old shook their head defiantly with their arms crossed.   
  


“I want to keep camping!” they signed with their hands. 

 

You sighed before replying, “Frisk, hon. I got work tomorrow. And you have school! We’re going home.” 

 

“I don’t want to go to school!” they replied. “I want to keep camping!”

 

“Frisk, your hearing aid got soaked in the lake and we need to find a replacement for it when we get back.” You cursed underneath your breath, knowing the cost of a new aid for Frisk. But you’ll have to deal with it when you get back.

 

You continue packing your things, zipping up a duffel bag filled with all of your clothes including Frisk’s. You moved the majority of your things back to the car; the last remaining things were your duffel bag and your tent. Wearing the straps of the duffel bag like a backpack, you say, “Dear, we need to go back. The sun’s about to go down and I don’t want to drive in the dark.” You turn to look at Frisk to see that they’re about 30 feet away from you, running.    
  
“Goddammit, Frisk!” you yelled. Hanging on to the straps of the duffel bag, you run after them. The distance doesn’t seem to get close and you see them reaching farther away before you see them stop inside a cave. “Frisk, what are you doing?! Come on,” you grab their shoulders to face them and start signing angrily. “You are going to sit down in the car and  **wait** and when I’m done packing, I-” 

 

Frisk tugs at your shirt before signing, “There’s something in there!” 

 

You stop in your tracks before turning to look at what Frisk glanced at. A giant hole in the earth with some parts covered in massive tree trunks. You walk back and glance before turning to look at Frisk, “What did you see?” you sign.

 

“A flower!” 

 

“We’re in a forest, Frisk. There’s flowers everywhere.”

 

“No, no, special flower!” they looked troubled, struggling to find the right word to describe the flower they saw. 

 

They ran back to where you were, overlooking the hole in the ground. You instinctively put your hand on Frisk, “You might fall,” you sign. “Let’s go home.” You grab Frisk’s hand again.

 

With their other hand free, they shake their head and sign, “No!” before taking a step backward and slipping into the hole.

 

“Frisk!” you cried out. You reached out your hand to try and catch them, but with the added weight of the duffel bag, you fall into to darkness yourself. 

 

\---

 

You wake up with a shrouded vision, there’s a faint but sweet scent in the air and a little bit of sunlight. You rub your eyes and evaluate your surroundings. There are massive yellow flowers around and underneath you and Frisk rests besides you. You think back to what happened and immediately started to wake up Frisk. “Hey! Hey buddy, you okay?” you ask, even though Frisk won’t be able to hear.

 

Frisk groans and shuffles before sitting up right, staring at you. They stare at you before staring above, putting their hand above their eyes due to the light shining down at them. You gain their attention by tapping them on the shoulder and sign, “Are you hurt anywhere? Are you in pain?” They shook their head and you let out a sigh. “Thank goodness,” you say aloud.

 

“What happened?” they sign.

 

“I think we fell down the hole from earlier.” You look at your surroundings and there is no possible way for you to climb up with Frisk. “This looks like a cave, let’s find our way out. Ok?” They nod and immediately holds your hand. 

 

You walk for a moment after passing what seemed to be a arched doorway before coming into another part of a cave. A large flower rooted into the ground with a smile on its face appeared. It looked at you for a moment before frowning and immediately went back to smiling. “Howdy!” it rang. “I’m Flowey. Flowey the Flower!” Frisk immediately starts pointing at it and tugging at your arm. It clicked in your head that this must have been the special flower they mentioned earlier. “Hmm. You’re new to the underground aren’tcha? Golly, you must be so confused.” 

 

Underground? You tilt your head in perplexion. 

“Someone ought to teach you how things work around here! I guess little old me will have to do.” It then winked, sticking its tongue out. “Ready? Here we go.”

 

All at once, a force pulls a heart out of your body. Bewildered, you gaze at its light, putting your hand to it. It’s warm to the touch and has a faint effect like a beating heart. You look to your side to see that Frisk also has a heart like object in front of them. The difference between yours and Frisk were the color; Frisk had a gorgeous crimson as yours was a faint pink.

 

“See that heart?” the flower asked, taking you out of your trance. “That is your SOUL. The very culmination of your being! Your SOUL starts off weak, but can grow strong if you gain a lot of LV. What’s LV stand for? Why, LOVE, of course!” Distraught from all this new information, you look at the flower for more answers. “You want some LOVE, don’t you? Don’t worry, I’ll share some with you!” It winked again with its tongue sticking out. 

 

Out of thin air, tiny, but apparent white pellets of light appeared around Flowey. “Down here, Love is shared through….little white “friendliness pellets.”” Beaming, the flower asks, “Are you ready?” the pellets come at your souls and Frisk instinctually moves to the side whereas you stay in place. The full brunt of the pellet hitting your soul is struck and you are brought down to your knees. You cling to your black sweater and you heave. Tears are brought to your eyes and when you look up, the flower has a sinister grin.

 

“You idiot,” it cackled. “In this world it’s kill or be killed. Why would anyone pass up an opportunity like this?” It looks at Frisk, “I’ll deal with you later. But first!” Dozens more bullets appear surrounding your soul like a ring. “ **Die.** ” It laughed as Frisk cried, clutching your arm. 

 

“Get out of here, Frisk!” You say out loud, forgetting their disability. “Run!” 

 

It’s maniacal laughter ends abruptly when a fireball is casted at it. Knocking the flower away from your sight. “What a terrible creature, torturing such a poor, innocent youth…” a voice calls out. You look up to find a beautiful creature before you. The creature had white fur, small horns, and a snout. You look up in shock and awe before they come closer, offering a hand to stand up. “Ah, do not be afraid, my children. I am Toriel, caretaker of the RUINS. I pass through this place every day to see if anyone has fallen down.” Shakingly, you accept the hand and stand up. She looks at you both before continuing, “You are the first humans to come here in a long time.” 

 

“Come!” she exclaims. “I will guide you through the catacombs.” She pivot turns and exits the cavern you were in. Taking Frisk’s hand, you follow after her. 

 

\---

About an hour later, you’ve successfully and peacefully navigated your way through the RUINS and are resting back at Toriel’s house. Frisk is asleep in one of the rooms and you sit on a nearby chair next to Toriel. Your soul is healing up as you slowly munch on a delicious slice of butterscotch cinnamon pie. “So…” you chirp, piquing Toriel’s attention. “I need to know this in advance. Are we in danger?”

 

Toriel doesn’t look up from her book, “Yes, but that can be avoided. Earlier you navigated your way peacefully and that can be done again. Establishing a sense of trust will help you avoid future fights with the monster residents that exist here. I’m certain you will adapt to coexist.” 

 

“Great, so just follow what we did earlier.” You look to the hallway on your side, wondering if Frisk is sleeping well. “Sorry, I’m just surprised Frisk didn’t want to sleep together. They went through something serious recently and haven’t been sleeping well.”

 

“Oh, I’m sorry,” she puts her paw on her mouth. “I’m certain that they will adjust in time.” You pause, unsure of what to discuss without potentially offending her.

 

“Excuse me, but…” you begin. “How do we leave the ruins?”

 

She doesn’t speak, but lets out a small sigh. “You are obviously not a child and I will respect that. However, it is too dangerous for you to leave the ruins. You will come across stronger monsters who will target you for being human. You need to stay here for your safety.”

 

“We need to get back up to the surface,” you interject. “Frisk has special needs. They need professionals who can tend to those needs up there.”

 

She opens her mouth to speak and pauses before asking, “What special needs are you talking about?”

 

“It may not have been all that noticeable, but Frisk can’t hear you.” You unzip your duffel bag to pull out a baggied hearing aid. “This device lets them hear, but it’s broken. That and we’re sort of going through a legal custody battle right now so they can stay in my care.”

 

“Well-” Toriel looks away from you and smiles. “Frisk!” 

 

Frisk sleepily rubs their eye and walks over to you, climbing on your legs before sitting on your lap. You rub their hair, trying to untangle small knots. “Should we keep discussing this or…” Toriel asks shyly.   
  
“It’s fine, they can’t hear anyways,” you remind her as you spoon-feed Frisk a portion of your pie. They sleepily take bites as they rest on you, chewing quietly. Frisk mumbles quietly as they chew; tired from their nap. 

 

“I still think it’s too dangerous for you two to venture out on your own. You’ll be safe here, with me.” Toriel declares.

 

“The Ruins is no place to raise a child,” you sigh, hoping to get this conversation over with. “I need to get them out of here before it’s too late.” Frisk tugs on your sleeve and with you spoon feed them another bite of pie. Toriel gazes at you both, feeling nostalgic and smiling sweetly. 

 

“Can I ask about the puzzles? What are they for?” you inquire.

 

“The puzzles are a monster tradition. Solving or creating complex puzzles is a sign of maturity to say that young monsters are capable of critical thinking. Not every monster does it, but it’s an enjoyable pastime for some.” She flips a page from her book. “So, may I inquire about Frisk? What is your relation to the child?”   
  


“Oh, they’re my cousin.” you feed Frisk another bite of pie. “I’m in this legal battle to have custody over them.”

 

“May I ask what happened to their parents?”

 

“I’d....rather not discuss it. I’m sorry.” Toriel nods understandingly before returning to her reading.

 

“Can you teach me more about souls? We don’t know anything related to magic on the surface.” Toriel looks up from her book in shock. “It’s a forgotten, somewhat condemned piece of history. I know I came from a line of witches, but I’m not sure if I have any magic in me.”

 

Smiling, Toriel says, “I’d be happy to teach you what I know. I’ll add it to the curriculum I have planned for Frisk. This may come as a surprise to you, but I have always wanted to be a teacher… Actually, perhaps that isn’t very surprising.” You chuckle in response. “Still, I am glad to have you both living here.”

 

After finishing the pie, Frisk starts falling asleep in your lap. “Oh boy,” you say aloud. “I think it’s time for someone to go back to sleep.” Toriel gets up from her chair and you pass her the empty plate and you pick up Frisk in your arms. “I’ll get Frisk to bed.”

 

Toriel nods, “I think it’d be time for you to rest as well.” You didn’t want to argue about staying here longer, but you did feel fatigued from the fighting/evading earlier. 

 

“One night,” you say. “And we have to go.” 

 

Toriel stays quiet as you walk away to the spare room she had prepared. You lie Frisk down before taking off your shoes. You lay next to them, careful of your position to not wake them. You wrap the blanket over their shoulder and they snuggle into it. 

 

It was one night then you would leave, you told yourself. Frisk had to go back to the surface by all means necessary.


End file.
